相关论文: A coherent double-quantum-dot electron pump
We investigate a mechanism for extracting heat from metallic conductors based on the energy-selective transmission of electrons through a spatially asymmetric resonant structure subject to ac driving. This quantum refrigerator can operate…
We study transport through a triple quantum dot in a triangular geometry with applied bias such that both singly- and doubly- charged states participate. We describe the formation of electronic dark states -- coherent superpositions that…
Manifestations of quantum coherence in the electronic conductance through nearly closed quantum dots in the Coulomb blockade regime are addressed. We show that quantum coherent tunneling processes explain some puzzling statistical features…
A major difficulty in realizing a solid-state quantum computer is the reliable measurement of the states of the quantum registers. In this paper, we propose an efficient readout scheme making use of the resonant tunneling of a ballistic…
We investigate transient transport of electrons through a single-quantum-dot controlled by a plunger gate. The dot is embedded in a finite wire that is weakly coupled to leads and strongly coupled to a single cavity photon mode. A…
We investigate sequential tunneling transport through a semiconductor double quantum dot structure by combining a simple microscopic quantum confinement model with a Mott-Hubbard type correlation model. We calculate nonperturbatively the…
In quantum metrology, semiconductor single-electron pumps are used to generate accurate electric currents with the ultimate goal of implementing the emerging quantum standard of the ampere. Pumps based on electrostatically defined tunable…
Quantum pumping through mesoscopic quantum dots is known to be enhanced by resonant transmission. The pumped charge is close to an integer number of electrons when the pumping contour surrounds a resonance, but the transmission remains…
As an alternative to commonly used electrical methods, we have investigated the optical pumping of charged exciton complexes addressing impurity related transitions with photons of the appropriate energy. Under these conditions, we…
Narrow line-widths and the possibility of enhanced spontaneous emission via coupling to microcavities make semiconductor quantum dots ideal for harnessing coherent quantum phenomena at the single photon level. So far, however, all…
Nanoscale single-electron pumps can be used to generate accurate currents, and can potentially serve to realize a new standard of electrical current based on elementary charge. Here, we use a silicon-based quantum dot with tunable tunnel…
We have measured the low-temperature transport properties of a quantum dot formed in a one-dimensional channel. In zero magnetic field this device shows quantized ballistic conductance plateaus with resonant tunneling peaks in each…
We consider pumping through a small quantum dot separated from the leads by two point contacts, whose conductances, $G_{1}$ and $G_{2}$, serve as pumping parameters. When the dot is pincched, we find that there is a "resonance line" in the…
We propose a random matrix theory to describe the influence of a time-dependent external field on electron transport through open quantum dots. We describe the generation of the current by an oscillating field for the dot, connected to two…
We consider quantum charge pumping of electrons across a superconducting double barrier structure in the adiabatic limit. The superconducting barriers are assumed to be reflection-less so that an incident electron on the barrier can either…
The influence of high-frequency fields on quantum transport through a quantum dot is studied in the low-temperature regime. We generalize the non crossing approximation for the infinite-U Anderson model to the time-dependent case. The dc…
We consider the full driven quantum dynamics of a qubit realized as spin of electron in a one-dimensional double quantum dot with spin-orbit coupling. The driving perturbation is taken in the form of a single half-period pulse of electric…
We propose a mechanism by which an open quantum dot driven by two ac (radio frequency) gate voltages in the presence of a moderate in-plane magnetic field generates a spin polarized, phase coherent dc current. The idea combines adiabatic,…
We study the charge current transmitted through the correlated quantum dot characterized by a finite magnitude of the Coulomb interaction |U|. At low temperatures the correlations can lead to appearance of the spin (for U>0) or charge (for…
We analyze quantum charge pumping in an open ring with a dot embedded in one of its arms. We show that cyclic driving of the dot levels by a \textit{single} parameter leads to a pumped current when a static magnetic flux is simultaneously…